Dynamic properties of Josephson junctions are interesting due to the emission of high
frequency radiation (up to THz range) from Josephson junctions, closely related to fluxon
dynamics. A better understanding of this dynamics can help to improve the Josephson devices
used for applications. Josephson junctions can also be of great use as T-shaped multiple
Josephson junctions in Josephson electronic circuits. In general, T-junctions consist of two
attached Josephson transmission lines: a main Josephson transmission line (MJTL) along the
-axis, and an additional Josephson transmission line (AJTL) along the -axis. These
junctions can use to create fluxons (solitons) in junctions without applied magnetic field,
(called flux cloning phenomenon). This work is devoted to contributing to a clarification of
the dynamic behaviour of solitons (fluxons) in 2D extended conventional T-shaped Josephson
junctions (extended means an AJTL is larger than MJTL). A conventional T-junction is a
MJTL along the x-axis which divides into two Josephson transmission lines along the x- and y-axes. In addition, we also attempt to elucidate further the concept of flux cloning in rotated
T-junctions, which are 90 degrees anticlockwise rotation of conventional T-junction. In rotated Tjunction,
a MJTL along the x-axis divide into two Josephson transmission lines along the y-axis. We find the first evidence of moving semifluxon and observe for the first time new
phenomena of semifluxons and anti-semifluxons in both extended conventional and rotated T-junctions.
We numerically study the electrodynamics behaviour of solitons in the standard Tshaped
Josephson junction (conventional T-junction) in a magnetic field. Therefore, we
describe theoretically how flux cloning circuits exist and give an opportunity for use as flux
flow oscillators operating without applied magnetic field. The results that emerge give further
support to the flux cloning mechanism.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.